The prior art describes the odorous properties, viz. the fixative characters, of 1-(2,6,6-trimethylcyclohexyl)-hexan-3-ol [see DE-AS No. 28 07 584, which corresponds to U.S. Pat. No. 4,252,986], also known under the name of 10-ethyl-tetrahydroionol. The prior art discloses further certain derivatives of the said compound, which derivatives contain either a branched, hydroxylic side-chain or a "shortened" hydroxylic chain possessing five carbon atoms [Dragoco Report 199 (1980)].
The above cited references, not only are mute as to the interest presented by compounds of formula (I), but also suggest that compounds other than 10-ethyl-tetrahydroionol possess fragrance properties significantly less developed than those shown by it.
It is with surprise therefore that we discovered that "methylated" compounds (I) not only possessed fragrance characteristics of great interest, but also that their properties were in effect superior to those shown by 10-ethyl-tetrahydroionol with respect to both their quality and their strength. We have discovered also unexpectedly that there existed a marked difference between the fragrance qualities of the distinct isomers of this series of compounds. Trans cyclanic isomers were judged far superior to their corresponding cis derivatives.
Whenever mention is made hereinafter to cis or trans cyclanic isomerism, we intend to refer to the particular configuration of the hydroxyhexyl group with respect to the methyl radical in position 6 of the hexanic ring.
One of the object of the present invention reverts to the use as perfuming ingredients of the compounds of formula (I) in their trans configuration or of mixtures containing proportions of more than 50% by weight of said compounds and less than 50% by weight of their corresponding cis isomers.
Furthermore, we could establish also that in the case of compounds (I) having R.sup.1 =ethyl and/or R.sup.2 =methyl, the specific isomers having at the same time the different substituents at positions 1, 2 and/or 3 and 6 of the hexanic ring in the equatorial configuration possessed odorous features more pronounced than those of their corresponding stereoisomers of opposite configuration.
Thus, for example, the compound of structure ##STR4## whose substituents in positions 1, 3 and 6 of the hexanic ring have the equatorial position, possesses a powerful odor of steroidal, animal, woody, or even ambery character. This odor character, accompanied by a sweaty note, is also found in the compound of formula ##STR5## having the methyl radical in position 3 in the axial configuration. Its odor strength however is less pronounced than that of the earlier compound.
Thanks to the present invention, it is now possible to prepare a product essentially consisting of the most olfactively interesting isomers.